This issue occurs when extension uses setEditorComponent. The
restoreEditor() callback was capturing this.editor AFTER
resetExtensionUI() (which restores defaultEditor), then adding that
captured editor back to the container - ignoring any new editor created
by extensions during session_start.
On success, use this.editor (may be custom editor from extension).
On failure, restore the fallback editor (safe defaultEditor state).
Rename restoreEditor to dismissLoader to reflect its actual purpose.